Method of production of half-tones.



J. v. RANOK. METHOD OF PRODUCTION OF HALF TONES.

APPLICATlON FILED APB..14, 1913.

Patented Aug. 25, 1914 JOHN V. RANCK, 0F BROOKLYN,

NEW YORK. ASSIGNOR T0 POWERS PHOTO ENGRAV- ING COMPANY, A CORPORATION OF NEW .YORK.

METHOD OF PRODUCTION OF HALF-TONES.

To all whom it may concern:

.Be it known that I, JonN V. RANCK, a

citizen of the United States, whose residence is 1618-.Beverly road, Flatbush, Brooklyn, New York, have invented certain new and useful Improvements in Methods of Production of Half-Tones, of which the following is a specification:

This invention relates to the production of half-tone reproductions, and has for its object to avoid the presence of dots in the high lights 1)" a method which is at once simple and effective. This method-is based on the preparation or production of an original in which the high lights, on the one hand, are of pronounced high actinic value, while the lower lights, or principal features, on the other hand, are of pronounced low actinic value, so that when this original is photographed through a screen onto a sensitized surface for a period calculated with reference to what may be termed the lowered lights the high lights are overexposed to such an extent as to eliminate the dots in these portions of the negative. This results in reproductions having white or clear high lights, without sacrificing anything in the quality of the other portions, and without resorting to complicated or time-consuming procedures' In the accompanying drawings illustrating the invention: Figure 1 represents an original, which in this instance will be understood to be an ordinary photograph. Fig. 2 is a view of the same, illustrating the next step in the process. All that has been done to the photograph is to apply a yellow wash or coating over the entire surface, as indicated by the hatching. Fig. 3 is a view of the same illustrating the final condition of the original. It is in the same condition as shown in Fig. 2, except that the high lights or such portions as are designed to be high lights have been painted white over the yellow. The white paint on the high lights has been represented in this view by leaving these portions entirely clear, so that what is really seen is the white surface of the paper. It will be understood that shadows may be applied in the background or elsewhere by simply applying black wherever desired. In this instance the shadow behind the figure is shown as being present in the photograph of Fig. 1, and in Specification of Letters Patent.

Application filed April 14, 1913.

' Patented Aug. 25, 1914. Serial No. 761,119.

Flgs. 2 and 3 is consequently covered with the yellow pigment.

In the preferred mode of procedure I first procure or be and usually is an ordinary photograph. This original I coat in the best embodiment of the invention is yellow pigment. Then I selectively treat or coat the high lights with a non-transparent substance of high actinic value, preferably white paint because of its high reflecting power, which is applied with a brush over the yellow coating, as indicated at a in Fig. 3. Of course, the non-actinic coating need not be applied to the highlightsin the first instance, but it is simpler and saves time to cover the whole surface with the colored wash.

Having produced an original having pronounced a-ctinic high lights and other portions of pronounced and relatively low actinic value, which other portions preferably include the principal features of the picture, such as the face, if the subject be an individual, I proceed to photograph it througha screen in the usual manner, with this exception that the length of the expo-- sure is calculated with reference to the lowered lights, so that by virtue of the actinic relation between the different portio-ns of the original the lowered lights are correctly photographed while the dots in the high lights of the negative are destroyed by overexposure. I

In making the photograph the aim is to bring out the principal feature or features, such, for example, as a face, clearly and distinctly. It will be observed that I may make any portion or portions of the picture high lights, whether naturally high lights or not, simply by coating these portions white in the original. The subsequent steps are or may be those usually followed, and the result, as already indicated, is the obtaining of reproductions having pure white lights.

What I claim as new is:

1. The method of obtaining half-tone reproductions devoid of dots in the high lights, which comprises producing an original having high lights of pronounced high actinic value and its lower lights of pronounced low-actinic value, and photograph produce an original, which may I all over with a trans-- parent substance of low actinic-value, which ing such original through a. screen onto a sensitized surface for a period of time sufficient to take such lower li 'hts correctly and to eliminate the dots in the high lights of the negative by overexposure.

2. The method of obtaining half-tone re-- productions devoid of dots in the high lights, which comprises coating an original positive with atransparent substance of relatively low actinic value, applying nontransparent coatings of high actinic value over the relatively non-actinic coating when clear high lights are desired, and photographing the original thus prepared through a screen onto a. sensitized surface with an exposure determined with reference to the port-ion of the original covered by the first coating outside of such high light portions.

3. The method of obtaining half-tone reproductions; devoid of dots in the high lights, which comprises coating the high lights of an original with a White substance of high actinic value and the lower lights with a yellow substance of low actinic value,

and photographing the original thus prepared through a screen onto a sensitized surface for a period of time sufiicient to correctly expose the principal features and to overexpose the high lights to an extent which causes the dots to disappear.

4. The method of obtaining half-tone reproductions devoid of dots in the high lights, which comprises lowering the low lightsor principal features of an original and reinforcing the high lights, andphotographing the original thus prepared through a screen onto a sensitized surface for a period of time sufiicient to correctly expose thepp'rincipal features and to. over-- expose the high lights to an extent which causes-the dots to disappear. v

In testimony whereof, I have signed my name to this specification, in the presence of. two subscribing Witnesses.

. JOHN-Y. RAN K-" Witnesses:

. r W. F. BISSING,

LUELLA Is. LITTLE. 

